##  [Kanban System](/kanban-system-0) 

 Definition

A visual pull-based inventory control method using physical or electronic cards, bins or signals to authorize production or replenishment of parts only when downstream demand consumes inventory, thereby limiting on-hand inventory and linking replenishment to actual usage.

 

 

 

 

 

 





## Principle

Principle

Kanban enforces production/replenishment only in response to realized demand signals from downstream operations; the number and type of kanban tokens define maximum allowed WIP and create a feedback loop that stabilizes flow by making shortages visible and timing replenishment to consumption.

 

 

 

 

 





## Demonstration

Demonstration

Illustrative scenario → A workstation uses two-card kanban for a subassembly: a production card at the supplier and a withdrawal card at the assembly cell. Recognition: when the assembly cell consumes a bin, it sends the withdrawal card to the supplier. Action: supplier produces one bin and returns the production card with the replenished bin. Consequence: inventory is limited to the number of cards, production matches consumption, and overproduction is avoided unless cards are increased.

 

 

 

 

## Misapplication

Misapplication

Interpreting kanban as a schedule or target rather than a real-time pull signal. The error is to let cards be treated as production quotas independent of actual consumption, which converts pull into disguised push and reintroduces overproduction and inventory growth.

 

 

 

 

 





## Consequence

Consequence

Proper kanban reduces inventory, exposes process problems quickly, shortens lead time and aligns production with customer demand; misused kanban can mask upstream variability, propagate shortages if card counts are too low, or produce instability if card rules are ignored or violated.

 

 

 

 

## Reversal

Reversal

When demand is highly variable and replenishment lead-times are long relative to consumption variability, strict kanban may lead to frequent stockouts; in such contexts, hybrid approaches (safety stock, time-based replenishment or larger lot kanbans) or calculated decoupling inventories may be necessary.

 

 

 

 

 





## Boundary

Boundary

Clearly within: a supermarket with fixed kanban cards controlling pull between fabrication and assembly. Boundary case: electronic kanban integrated with ERP—functionally kanban but dependent on data latency and system availability. Clearly outside: forecast-driven push schedules (MPS) that release work by planned dates rather than consumption signals.

 

 

 

 

 





## Semantic Tension

Semantic Tension

Inventory Minimization ↔ Service Level: reducing kanban card counts lowers inventory but increases risk of stockout and service-level degradation; managers must set kanban quantity to balance working capital and acceptable fill rates.

 

 

 

 

 





## Synthesis

Synthesis

Kanban is a control mechanism that converts actual consumption into bounded production authority; its effectiveness depends on choosing appropriate signal granularity, card count and replenishment lead-time, and on maintaining discipline so that pull remains responsive rather than becoming a routinized schedule.